ComboBox and key listener?

Vaadin 6 / 7 / 8 Framework UI
1

Is it possible to attach a key listener to a ComboBox? Currently, I’m using a ComboBox with a NewItemListener:

ComboBox c = new ComboBox();
c.setNewItemsAllowed(true);
c.setImmediate(true);
c.setNewItemHandler(new NewItemHandler() {
  public void addNewItem(String newItemCaption) {
    c.addItem(newItemCaption);
    c.setValue(newItemCaption);
  }
});

When entering a new value into the Combox, an event for inserting the value is triggered as soon as the ComboBox looses its focus. What I’m trying to achieve is that the user has to press the Enter key in order to add the value to the ComboBox. Does anyone know who this can be done?